In general, the number of vehicle articles using electricity in vehicles is gradually increased due to the development of electronic devices and consumption of electric power is increased accordingly.
In the prior art, when starting a vehicle with a main battery installed in the vehicle, electric power of the main battery is used. After the start-up, a generator connected to an engine generates electric power to charge the main battery, so the electric power is supplied to various electric articles/components. In this case, generated electric power is limited. Thus, if lots of electric articles (a fan for an air conditioner, a fan for seat air conditioning, an air cleaner, an ion generator, an oxygen generator, air conditioning and heating equipment, cooler and warmer, various AV devices, etc.) are used, there are shortcomings in that the output of the vehicle was lowered, fuel consumption was increased, and excessive load is applied to the vehicle and the main battery. When the main battery is discharged, there is no solution to prevent such discharge.
Further, there are lots of problems in that when the vehicle is not started, various electric articles cannot be used because electric power of the main battery is limited.
In order to solve the problems, technologies employing a solar cell have been developed. Among them, in U.S. Pat. No. 6,439,658, the solar cell arrangement is attached on the solar roof and the ventilation fans are installed in the vehicle seats. When the vehicle is parked, the seats are ventilated using electric power generated from the solar cell arrangement in order to drop the temperature of the seats. The ventilation fans for the seats are controlled by a controller. The fans are driven to lower the temperature of the seats using the temperature sensors of the seats. Further, when there is surplus electric power, electric power is supplied to the vehicle blower in order to ventilate the vehicle interior.
Furthermore, in U.S. Pat. No. 6,290,593, when the engine of a vehicle is stopped, electric power generated from the solar cell is supplied to the vehicle ventilation fan or is used to charge the battery of the vehicle. Further, a user uses electric power, generated from the solar cell, to ventilate the vehicle or to charge the battery using a switch that is manually operated.